Use multiple instance of same lookup

I have a source Oracle table(S) For Training data with following 2 Fields
Instructor_Name Participant_Name
I1 , P1
I1 , P2

There is another table(L) in a different DB having Id for both Instructor & Participant
Id Name
1 , I1
2 , P1
3 , P2

In Target Table I want to populate following fields
Instructor_ID Participant_ID
1 , 2
1 , 3

Is there a good way to do this without doing lookup on L twice?